In combination with abasic site (AP site)-containing oligodeoxynucleotides (ODNs), a potential use of a hydrogen bond forming ligand, 2-amino-7-methyl-1,8-naphthyridine (AMND), has been demonstrated for the fluorescence detection of the cytosine (C)/guanine (G) mutation sequence of the cancer repression gene p53. An AP site-containing ODN is hybridized with a target ODN so as to place the AP site toward a target nucleobase, by which hydrophobic microenvironments are provided for ligands to recognize target nucleobases through hydrogen-bonding. To increase the binding constant, a methyl group was attached to AMND and its detection ability for SNPs was examined. As a result, high affinity was achieved as expected. The effect of the structure of a hydrophobic site in an oligo-DNA duplex on the affinity was also examined.Potential use of a surfactant-like receptor is demonstrated at the 1,2-dichloroethane-water interface for strong and selective binding of H_2PO_4^-over Br^-and Cl^-. The a
… Morenalysis by interfacial tensiometry reveals that the interfacial adsorption of a thiourea-isothiouronium conjugate, BT-C1, is significantly stabilized by the binding of H_2PO_4^-with the adsorption constant of 1.7x10^5 M^<-1>, while the interfacial adsorptivity of this receptor is relatively moderate for Br^-and Cl^-. Such complexation-induced interfacial adsorption behaviors of BT-C1 are discussed as a basis for the development of receptor-based chemical sensors for phosphate anions A mesoporous membrane composed of nanochannels with a uniform diameter has a potential use for precise size-exclusive separation of molecules. Here, a novel method is reported to form a hybrid membrane composed of silica-surfactant nanocomposite and a porous alumina membrane, by which size-selective transport of molecules across the membrane becomes possible. The nanocomposite formed inside each columnar with nanocompositesAlumina pore was an assembly of surfactant-templated silica-nanochannels with a channel diameter of 3.4 nm ; the channel direction being predominantly oriented along the wall of the columnar alumina pore. Molecules could be transported across the membrane including the silica-surfactant nanocomposite with a capability of nanometer-order size-exclusive separation. Our proposed membrane system has a potential use not only for separation science, but also catalysis and chip technologies. Less